Project Summary/Abstract This proposal is a competing renewal application of the Northeast Node of the National Drug Abuse Treatment Clinical Trials Network (CTN), which joined the CTN in 2015. The Northeast Node brought hundreds of community and healthcare partners across the states of New Hampshire, Vermont, and Maine to the CTN community for the first time. These states have among the very highest rates of substance use in the U.S., including opioid use, and they include some of the most rural communities in the U.S. The Node has brought significant expertise to the CTN in conducting practical, rigorous, innovative, and highly impactful trials focused on improving the treatment of substance use disorders (SUDs) in community systems in the Northeast and in partnership with other CTN Nodes across the nation. Node Investigators have extensive experience in leading national and multi-national clinical trials, digital technology; medication and behavioral treatments for opioid use disorder; co-occurring SUDs and mental health disorders; SUD and chronic pain; SUD in pregnant women; opioid, cannabis, tobacco, alcohol, stimulant, and polydrug treatment; SUD prevention and treatment among youth; and implementation science. The Northeast Node is embedded within the Center for Technology and Behavioral Health (CTBH), a NIDA-funded P30 ?Center of Excellence?. The Node thus brings significant expertise in developing, evaluating, and implementing digital treatments for SUDs, with a focus on overcoming the striking disparities in treatment access and treatment quality evident in healthcare across the globe. In the renewal period, the Node proposes to enhance its activities and contributions to the national CTN to embrace advances in scientific discovery and research innovations that offer great promise for increasing the reach and effectiveness of treatments for SUDs. The Node will engage a broader group of investigators that bring additional expertise in data science (bioinformatics, predictive modeling, artificial intelligence, social media, data privacy/security) and experimental design (micro-randomized trials, adaptive designs, and implementation/systems science). With this expanded group of partners, it will support and grow a productive research agenda in the CTN with a focus on (a) digital health and data analytics, including research focused on providing personalized, science-based resources to individuals with SUD via digital technology and (b) expanding low threshold access to science-based SUD care, particularly in rural contexts (e.g., general medical settings; pharmacies; and community organizations). And the Node will lead an expansion of CTN research on the (c) rapidly evolving landscape of cannabis use as well as (d) co-morbid SUD and mental health disorders. The Node will establish Community and Policy Advisory Boards to complement the existing communication infrastructure between Node investigators and their partners, with a focus on identifying the most significant and timely SUD needs in our communities and scaling-up and sustaining best practices.